Event Notification Report for March 16, 2018
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
03/15/2018 - 03/16/2018
EVENT NUMBERS
53267
!!!!! THIS EVENT HAS BEEN RETRACTED !!!!!
!!!!! THIS EVENT HAS BEEN RETRACTED !!!!!
Power Reactor
Event Number: 53267
Facility: BROWNS FERRY
Region: 2 State: AL
Unit: [1] [2] [3]
RX Type: [1] GE-4,[2] GE-4,[3] GE-4
NRC Notified By: DREW MITCHELL
HQ OPS Officer: DAVID AIRD
Region: 2 State: AL
Unit: [1] [2] [3]
RX Type: [1] GE-4,[2] GE-4,[3] GE-4
NRC Notified By: DREW MITCHELL
HQ OPS Officer: DAVID AIRD
Notification Date: 03/16/2018
Notification Time: 22:04 [ET]
Event Date: 03/16/2018
Event Time: 00:00 [CDT]
Last Update Date: 11/29/2018
Notification Time: 22:04 [ET]
Event Date: 03/16/2018
Event Time: 00:00 [CDT]
Last Update Date: 11/29/2018
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(ii)(B) - UNANALYZED CONDITION
10 CFR Section:
50.72(b)(3)(ii)(B) - UNANALYZED CONDITION
Person (Organization):
REBECCA NEASE (R2DO)
REBECCA NEASE (R2DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | N | Y | 100 | Power Operation | 100 | Power Operation |
| 2 | N | Y | 100 | Power Operation | 100 | Power Operation |
| 3 | N | N | 0 | Refueling | 0 | Refueling |
UNANALYZED CONDITION AFFECTING RESIDUAL HEAT REMOVAL SYSTEM
"At 1604 [CDT] on March 16, 2018, Browns Ferry Nuclear Plant (BFN) Engineering reported an unanalyzed condition affecting the Residual Heat Removal (RHR) heat exchangers in a postulated fire event. It was discovered that the Residual Heat Removal Service Water (RHRSW) heat exchanger piping associated [with] the credited heat exchangers in the NFPA 805 Nuclear Safety Capability Analysis (NSCA) could experience water hammer damage.
"Fire damage to the cables for the RHRSW outlet motor operated valves could cause the valves to spuriously open and drain the RHRSW piping. Subsequent starting of the RHRSW pumps on the affected header could cause water hammer loads and damage the piping.
"Review of NFPA 805 analyses show the cables associated with this condition are routed in Fire Areas 01-03, 02-03, 02-04, 03-03, 16 and 23. There are 11 cases where the deterministically credited heat exchanger could be affected.
"Compensatory fire watch measures have been established.
"This event requires an 8 hour report in accordance with 10CFR50.72(b)(3)(ii)(B), 'Any event or condition that results in: (B) The nuclear power plant being in an unanalyzed condition that significantly degrades plant safety.
"CR 1139620 documents this condition in the Corrective Action Program."
The NRC Resident Inspector has been notified.
* * * RETRACTION AT 2215 EST ON 11/29/2018 FROM NEEL SHUKLA TO MARK ABRAMOVITZ * * *
"NRC notification 53267 was made to ensure that the eight-hour non-emergency reporting requirements of 10 CFR 50.72 were met when the licensee discovered an unanalyzed condition with the potential to significantly degrade plant safety.
"On August 22, 2018, an independent analysis was completed which determined that the RHRSW system would remain functional during the postulated scenario. Based on this analysis, a revised functional evaluation was performed by BFN which determined that the condition did not constitute an unanalyzed condition that significantly degraded plant safety. For credited RHR heat exchangers for fire events in Fire Areas 01-03, 02-03, 02-04, 03-03, 16, and 23, the RHRSW piping will remain intact and the valves will operate manually after a water hammer event. This condition did not significantly degrade plant safety and is therefore not reportable under 10 CFR 50.72(a)(2)(ii)(B).
"On November 16, 2018, TVA canceled the 60 day report which had been submitted for this condition.
"TVA's evaluation of this event notification is documented in the corrective action program.
"The licensee has notified the NRC Resident Inspector."
Notified the R2DO (Shaeffer).
"At 1604 [CDT] on March 16, 2018, Browns Ferry Nuclear Plant (BFN) Engineering reported an unanalyzed condition affecting the Residual Heat Removal (RHR) heat exchangers in a postulated fire event. It was discovered that the Residual Heat Removal Service Water (RHRSW) heat exchanger piping associated [with] the credited heat exchangers in the NFPA 805 Nuclear Safety Capability Analysis (NSCA) could experience water hammer damage.
"Fire damage to the cables for the RHRSW outlet motor operated valves could cause the valves to spuriously open and drain the RHRSW piping. Subsequent starting of the RHRSW pumps on the affected header could cause water hammer loads and damage the piping.
"Review of NFPA 805 analyses show the cables associated with this condition are routed in Fire Areas 01-03, 02-03, 02-04, 03-03, 16 and 23. There are 11 cases where the deterministically credited heat exchanger could be affected.
"Compensatory fire watch measures have been established.
"This event requires an 8 hour report in accordance with 10CFR50.72(b)(3)(ii)(B), 'Any event or condition that results in: (B) The nuclear power plant being in an unanalyzed condition that significantly degrades plant safety.
"CR 1139620 documents this condition in the Corrective Action Program."
The NRC Resident Inspector has been notified.
* * * RETRACTION AT 2215 EST ON 11/29/2018 FROM NEEL SHUKLA TO MARK ABRAMOVITZ * * *
"NRC notification 53267 was made to ensure that the eight-hour non-emergency reporting requirements of 10 CFR 50.72 were met when the licensee discovered an unanalyzed condition with the potential to significantly degrade plant safety.
"On August 22, 2018, an independent analysis was completed which determined that the RHRSW system would remain functional during the postulated scenario. Based on this analysis, a revised functional evaluation was performed by BFN which determined that the condition did not constitute an unanalyzed condition that significantly degraded plant safety. For credited RHR heat exchangers for fire events in Fire Areas 01-03, 02-03, 02-04, 03-03, 16, and 23, the RHRSW piping will remain intact and the valves will operate manually after a water hammer event. This condition did not significantly degrade plant safety and is therefore not reportable under 10 CFR 50.72(a)(2)(ii)(B).
"On November 16, 2018, TVA canceled the 60 day report which had been submitted for this condition.
"TVA's evaluation of this event notification is documented in the corrective action program.
"The licensee has notified the NRC Resident Inspector."
Notified the R2DO (Shaeffer).